#include "stack.h"
#include "queue.h"
#include "iostream"

int main() {
    lwj::queue<int> q;
    lwj::stack<int> s;
    s.push(1);
    s.push(2);
    s.push(3);
    s.push(4);

    cout<< s.size() << endl;
    s.top() = 5;
    while (!s.empty())
    {
        int x = s.top();
        s.pop();
        cout<<x<<' ';
    }
    cout<<endl;
    return 0;
}
